[PATCH v18 QEMU 02/18] vfio: Add function to unmap VFIO region

[Kirti Wankhede <kwankhede@nvidia.com>]

This function will be used for migration region.
Migration region is mmaped when migration starts and will be unmapped when
migration is complete.

Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Reviewed-by: Neo Jia <cjia@nvidia.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
---
 hw/vfio/common.c              | 20 ++++++++++++++++++++
 hw/vfio/trace-events          |  1 +
 include/hw/vfio/vfio-common.h |  1 +
 3 files changed, 22 insertions(+)

diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index 0b3593b3c0c4..4a2f0d6a2233 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -983,6 +983,26 @@ int vfio_region_mmap(VFIORegion *region)
     return 0;
 }
 
+void vfio_region_unmap(VFIORegion *region)
+{
+    int i;
+
+    if (!region->mem) {
+        return;
+    }
+
+    for (i = 0; i < region->nr_mmaps; i++) {
+        trace_vfio_region_unmap(memory_region_name(&region->mmaps[i].mem),
+                                region->mmaps[i].offset,
+                                region->mmaps[i].offset +
+                                region->mmaps[i].size - 1);
+        memory_region_del_subregion(region->mem, &region->mmaps[i].mem);
+        munmap(region->mmaps[i].mmap, region->mmaps[i].size);
+        object_unparent(OBJECT(&region->mmaps[i].mem));
+        region->mmaps[i].mmap = NULL;
+    }
+}
+
 void vfio_region_exit(VFIORegion *region)
 {
     int i;
diff --git a/hw/vfio/trace-events b/hw/vfio/trace-events
index b1ef55a33ffd..8cdc27946cb8 100644
--- a/hw/vfio/trace-events
+++ b/hw/vfio/trace-events
@@ -111,6 +111,7 @@ vfio_region_mmap(const char *name, unsigned long offset, unsigned long end) "Reg
 vfio_region_exit(const char *name, int index) "Device %s, region %d"
 vfio_region_finalize(const char *name, int index) "Device %s, region %d"
 vfio_region_mmaps_set_enabled(const char *name, bool enabled) "Region %s mmaps enabled: %d"
+vfio_region_unmap(const char *name, unsigned long offset, unsigned long end) "Region %s unmap [0x%lx - 0x%lx]"
 vfio_region_sparse_mmap_header(const char *name, int index, int nr_areas) "Device %s region %d: %d sparse mmap entries"
 vfio_region_sparse_mmap_entry(int i, unsigned long start, unsigned long end) "sparse entry %d [0x%lx - 0x%lx]"
 vfio_get_dev_region(const char *name, int index, uint32_t type, uint32_t subtype) "%s index %d, %08x/%0x8"
diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h
index fd564209ac71..8d7a0fbb1046 100644
--- a/include/hw/vfio/vfio-common.h
+++ b/include/hw/vfio/vfio-common.h
@@ -171,6 +171,7 @@ int vfio_region_setup(Object *obj, VFIODevice *vbasedev, VFIORegion *region,
                       int index, const char *name);
 int vfio_region_mmap(VFIORegion *region);
 void vfio_region_mmaps_set_enabled(VFIORegion *region, bool enabled);
+void vfio_region_unmap(VFIORegion *region);
 void vfio_region_exit(VFIORegion *region);
 void vfio_region_finalize(VFIORegion *region);
 void vfio_reset_handler(void *opaque);
-- 
2.7.0